Businesses which utilize communication networks may transmit data using both wire line and wireless technologies such as radio frequency (RF) or infrared (IR) communications. Since the data may be of a proprietary nature, it is often desirable to keep it secret (i.e., free from unauthorized detection). One solution is to restrict access within the network of concern.
FIG. 1 illustrates a communications network comprising wireless LAN 100 having a central controller or access point (AP) 10 that utilizes RF communications to communicate with a number of user devices (UDs) 12, such as portable computers, lap-top computers, personal digital assistants (PDAs) and the like. In the illustrative network, AP 10 is also connected to data network 14 by data channel 16 which may include, but is not limited to wires or optical links.
AP 10 controls communication within the illustrated network and passes information between data network 14 and the plurality of devices 12 within its zone of RF coverage. The information is conveyed in the form of packets. Data network 14 may consist of an Ethernet network, a Token Ring network or any other of the well known voice and/or data networks.
Access to the wireless LAN 100 is typically controlled by AP 10, in response to UD 12 requests. During operation, a password is entered into a UD seeking access within LAN 100. In response to the password, the UD will select a key and a polynomial. Thereafter, packets received by and transmitted from that UD are encrypted via the selected key and polynomial. Communications is permitted if the UD selected key and polynomial is identical to the key and polynomial used by the servicing AP 10. For additional information on a method for selecting key and polynomial values for use during encryption, the interested reader is directed to U.S. Pat. No. 5,199,072, filed Feb. 3, 1992 and assigned to the assignee of the present invention.
Under this scenario, only authorized UDs (i.e., those utilizing the proper key and polynomial) will be able to communicate within LAN 100. Once an authorized UD gains access to LAN 100, it has unlimited access to the entire network connected to AP 10. In many instances, however, it will be desirable to limit the type of access and services offered particular UDs. This is especially true when LAN 100 is deployed in an office environment.
In an office, some employees seeking to access LAN 100 will require full and complete access to network information, capabilities and services. Others will not. Likewise, when a UD 10 is being operated in the office by a non-employee or guest, it is typically undesirable to provide such individuals with full and complete access to ones internal communications network.
It would be extremely advantageous therefore to provide an access methodology supporting the establishment of multiple classes of users (i.e., UDs 10). Some user classes will have unlimited access to the network, others will not. In addition to different access capabilities, the level of service offered to users within the various classes may also differ.